Vain Head and Double Heart
by HerHighness
Summary: John Watson has a problem: he hasn't met his soul mate. Moreover, his TiMER hasn't even activated yet. Somehow he still finds himself falling deeply in love with his nutter of a flat mate. Meanwhile, the emotionally oblivious Sherlock investigates a case. TiMER universe ("If a clock could count down to the moment...") and soul mate AU. Also, a bit of a case fic. T for language.


**A/N: **The lovely Naked-Running here on FFN has graciously done a Chinese translation of this! A link to Naked-Running's profile and story are available on my profile page.

* * *

"_If a clock could count down to the exact moment you meet your soul mate, would you want to know? That's the claim of manufacturers of a new device called the 'TiMER'. The next evolutionary step in computer match-making, the TiMER lets you know when your perfect match has entered your life."_

"_We've discovered that all humans are on a path to true love. Implanted, just after the onset of puberty, and powered by body heat, the TiMER monitors levels of oxytocin, the hormone of love."_

"_It zeros out at midnight the night before, and then, the next day, it could go off at any second, and you meet your soul mate!"_

_ -TiMER (2009)_

* * *

John Watson was not having a good day. He woke up, bleary-eyed from an insufficient amount of sleep both that night and cumulatively over the past week, to a strange odor permeating the flat. Sighing and rubbing a hand over his face, John got up and followed the smell to the source, which was, of course, the kitchen.

"What's all this, then?" The doctor directed towards his nutter of a flat mate, who stood over a bounty of chemicals and equipment.

"I presume you're referring to the scent. That would be acetic anhydride, one of the key components in synthesizing acetylsalicylic acid." Sherlock turned slightly toward him, shooting one of his signature reproachful looks. "Really, John. You're a doctor; you should know this."

"Right, of course." He rolled his eyes. Yes, _clearly_ he should be able to identify specific chemicals by smell. "And why are you making aspirin in our kitchen again?"

"Case."

"Yeah, ta, I gathered that much. Would you like to elaborate?"

"Comparing the effects of a poorly-created homemade version with a 23% yield and its effects on blood thickness, pain, and allergic reactions to that of acetylsalicylic acid in its pure, marketed form. Need to determine how long and in what quantity it was administered before death." Sherlock's voice was monotonous, his words spilling out as he swirled an Erlenmeyer flask rapidly in his right hand.

John, of course, was quite use to the experiments and over-all bizarre behavior of his friend, but that didn't mean he particularly appreciated being assaulted by the smell of pungent, corrosive, _flammable_ chemicals. "Just… try not to burn down the flat."

After a not-so-reassuring "Hmm" in response, John let out another weary sigh and began to get ready for work.

* * *

The clinic was not much better. Though he truly enjoyed being a doctor, John was not well-suited to inane, menial tasks, like diagnosing strep throat or prescribing antibiotics. Unfortunately, he faced an abundance of exactly that. Apparently, it was going around again.

His day took an especially poor turn when, as he was switching patients, he heard the unmistakable pinging of two TiMERs going off.

Hurriedly, and mostly out of habit, John pushed the edge of his left sleeve away from his wrist and glanced at the device.

No. No, of course it wasn't.

His TiMER continued to flash defiantly with dashes, as it had done since he got it at 18 (a fairly unwelcome birthday present from his sister, who had always loved both new technology and romance), signifying that his soul mate still hadn't even _installed_ a TiMER of their own.

Glancing up, he cringed as he realized the happy couple was a pair of teenagers who probably just got their TiMERs installed last week. The pair of gangly teens embraced in the lobby of the clinic as their parents introduced themselves and gushed over the scene.

Fate was a sick fuck.

John had had his TiMER for almost twenty years, and was beginning to give up hope that his perfect match would ever just bloody get one so at least he'd have a clue as to how much longer it'd be. He'd occasionally contemplated just getting his own removed so that he wouldn't have to continue paying the monthly bills for a useless device. The only thing stopping him was that he knew removal was permanent; he couldn't just have it reinstalled if he changed his mind.

Readjusting his sleeve, John walked over to congratulate the pair along with his coworkers. He really couldn't begrudge them. Finding one's soul mate was a joyous time, and Leslie and Lauren seemed like very sweet kids.

Sarah Sawyer touched his arm and smiled sympathetically as he passed. His lovely boss had been in the same unfortunate position as him when he'd first started working at the clinic, and they'd tried to make it work between them.

It had been going rather well, until Sarah's TiMER had started up in the middle of one of their dates. She still had about four years to wait at that point. They had contemplated continuing their budding relationship for a bit longer, but that felt too pointless to both of them. They ended on fairly good terms, but that didn't stop Sarah from feeling bad about the whole debacle.

"John-"

"How much longer now, Sarah?"

She flinched, knowing that he was trying to deflect. "Just under four months to go. But John, it'll happen for you, too. You're a good man. Whoever your soul mate is, they'll be very, very lucky to have you."

"Thanks." John really meant it. It certainly was a shame that things hadn't worked out with Sarah; she was a true gem. "Yours will be lucky, too, you know." He reached out and placed a hand on her shoulder, squeezing gently before shuffling back to his office.

Pinching the bridge of his nose, he grabbed his mobile and shot off a text to Greg.

_Drinks tonight? –JW_

John knew he shouldn't. Alcohol was neither a healthy nor effective means of dealing with emotions, but sometimes it was the only method he could handle.

_Sure. Is this about Sherlock? –GL_

_For once, no. –JW_

Though, in a roundabout sort of way, it was. Maybe it was the loneliness or maybe he was just going mad, but John had slowly, steadily, surely been forming a _thing_ for his flat mate. Honestly, who could blame him? Sherlock was tall, handsome, a veritable genius. Yes, he had a few… quirks, but he was still the best man that John knew, and he was certainly the best friend that John had ever had.

But prolonged exposure to the great detective's charms have left him wanting a bit more than the man's friendship. Really, John thought, it was a bad lot, having a _thing_ for Sherlock Holmes. The git practically oozed condescension for basic human interaction, let alone romantic entanglements.

All the more reason to yearn for his soul mate, he supposed. The sooner his soul mate entered his life, the sooner he could get the hell over Sherlock bloody Holmes.

* * *

When John arrived at the pub, Greg was already waiting for him at their usual spot, with two beers sat in front of him.

"Sorry I'm late. These two kids timed out in our office today, and it set our schedule back a bit more than I was anticipating."

"No problem, mate," the DI said as he passed one of the mugs to John. "Always nice when they get to meet young. I know I was disappointed when I got my TiMER and saw I'd be well over 30 before I met mine. Well worth the wait, though, of course."

John grumbled "Christ, I hope so," into his beer before chugging down a large amount of the ale.

Greg cleared his throat and fiddled with his shirt collar a bit, looking rather uncomfortable. "So… you and Sherlock on a case right now?"

"_He_ is. He's looking into the Walker case."

"You mean the man who died from anaphylactic shock?" His eyebrows knit together in confusion.

"That's the one." Another swig.

"But that was a suicide! For God's sake, the man was found in his home with an empty bottle of aspirin in his hand and an unused EpiPen within arm's reach!"

John shrugged. "Sherlock said it didn't make sense – something about his tie. Anyway, he tested the man's blood yesterday. Apparently, the salicylic acid that he reacted to wasn't from the aspirin found in his hand, but some homemade stuff. I woke up this morning to that prat stinking up the flat with some experiments for it." Lestrade smirked, hearing the fond exasperation in John's tone. "Anyway, there's not much I can do to be of any help right now, so I'm planning on putting in some extra time at the clinic so my boss actually keeps me on staff for a bit longer."

"It's a damn miracle you've stayed on as long as you have, with how frequently you and Sherlock run off for a case."

"True," John laughed, "but Sarah's a saint. Mostly, I think she keeps me around because she still feels bad about how it ended between us." He smiled ruefully and downed the rest of his drink, gesturing almost immediately for another.

Greg's eyes widened. "You dated your boss?"

"Yeah, well," he rubbed at his neck, "it was a while back. It seemed like a good idea at the time, you know? Neither of us had activated yet, and we were both rather lonely. Like I said, she's a saint. We got on well. Until her TiMER started up in the middle of one of our dates."

"Oh, mate, I'm sorry. That must have been awful."

The bartender sat another mug in front of him, and John promptly took a long drink. "It was unfortunate timing, but it was bound to happen eventually."

"It's hard to believe she still feels bad about it, though. I mean, everything turned out for the best."

John scrunched his nose up. "Yeah, I suppose," he droned, grimacing a bit.

Lestrade promptly looked uncomfortable again. "John-"

"How did you meet your soul mate, Greg?"

The DI was taken aback by this sudden interruption, but managed to force out a laugh. "John, I don't think we're quite drunk enough for this sort of conversation." John just gazed into his beer forlornly, so Lestrade decided to swallow his concern. "We met through a case. There was nothing particularly uncommon about it. Our eyes met, our TiMERs went off, we introduced ourselves, began dating, fell madly in love, eventually got married. The usual." He shrugged, smiling softly at the memory.

"Was it everything you'd hoped for?"

"And more, as the saying goes." His smile dropped. "John, where is all this coming from? I thought you said this wasn't about Sherlock?"

"Of course it's about Sherlock," John snapped spitefully. "My entire bloody life centers around that wanker! And now I think I've gone and fallen in love with him, and, Jesus Christ, what the hell am I supposed to do now?"

"John," Lestrade said slowly, growing more concerned over his friend, "I'm honestly not sure why you're so worried about this. It's a completely normal thing that-"

He laughed without an ounce of humor. "Normal? How on Earth is anything about this normal? I'm in love with a man who told me, within twenty-four hours of meeting me, that he is married to his work!"

"Jesus," Lestrade cringed. "He really said that?"

John laid his head down on the table and groaned.

"Look, Sherlock is a pretentious asshole. No one can deny that. But you'd have to be blind not to see how much you've changed him. And, you know, the TiMER is never wrong."

"The TiMER!" He exclaimed, throwing his hands up in exasperation. "That's the goddamn problem! On one hand, I can't imagine not living with Sherlock and solving crimes and waking up to the smell of dangerous chemicals, but on the other hand, if I could meet my soul mate or even just have some real bloody proof that they are out there somewhere, maybe I could get over this stupid, masochistic fixation on my fucking flat mate!"

There was a long pause in the conversation, before John finally looked over at Lestrade curiously. He was sitting perfectly still, a look of pure shock etched on to his face.

"What?" John asked, equal parts annoyed and anxious.

"You mean… you said… You _haven't met_ your soul mate yet?"

"Jesus Christ, Greg! Where the hell have you been? Why would you think – _Who_ would you think..." He froze. "You thought… all this time, you thought Sherlock and I…" John's voice was ice.

"John," the DI tried to sooth.

"No. Fucking—am I that obvious? I mean… Shit. I've gotta go."

Lestrade stood. "No, it's not-"

"Thanks for coming out on such short notice, Greg. I'll see you around." He threw some money down on the table and made for the door.

"John, wait!" But it was too late. He was already out the door and storming down the street. Lestrade collapsed heavily back into the booth. "Bloody hell," he murmured, chugging the last of his beer and burying his face in his hands.

* * *

Sherlock Holmes was not having a good day. The Walker case was proving more challenging than he had anticipated. Sure, it was a fairly simple task to synthesize and test some common acetylsalicylic acid; he could have done it when he was in primary school. No, the cause of death was all too easy to figure out.

His experiments revealed just what he had suspected. The lower concentration of salicylic acid, Walker's allergen, had slowed down his death marginally. Aspirin would have taken approximately 20 minutes to take effect, but the concoction in Walker would have caused the reaction to occur in 40 minutes or more.

But why? Why would someone go to the effort to make a watered-down version of aspirin and administer it to Walker in order to slow down the reaction time, then set it up to look like a suicide?

Obviously, the extra time was needed to get Walker away from the scene of the crime, which means that it occurred somewhere public, and recognizable. But if it occurred in public, why didn't anyone stop the assailant? Surely, someone would notice someone forcing something down another man's throat. Or, at the very least, hear Walker's pleas for help. 40 minutes is a long time for a victim to be silent about the attack, especially if the attacker is trying to put distance between them. Not to mention, Walker had an EpiPen.

So why didn't he use it? The obvious answer is that the attacker took it, but, again, he had 40 minutes to get a new one. So then, he didn't know he was administered the allergen until it was too late to get a new one.

But how could someone administer a homemade pseudo-aspirin in a public setting without the victim or anyone else knowing?

* * *

When John finally made it back to the flat, he had calmed down significantly. He had decided that even if his feelings for his flat mate were obvious, it clearly wasn't a problem. If Sherlock knew and just hadn't said anything, he apparently wasn't bothered by it. Sherlock didn't make a habit of neglecting to point out things that bothered him, after all. And if he was oblivious, as Sherlock seemed to be about most things concerning emotions, then no harm was done. John was simply overreacting. Yes. That's it. Just overreacting.

All the same, he walked slowly up the stairs to 221B. Determined to keep things seeming natural, he called out "I'm home" as he hung his coat up.

"Hmm..." Sherlock replied, sitting with hands steepled over his mouth.

"How's the case?"

Sherlock looked up at him, eyes narrowed as he deduced. "How was the argument with Lestrade?"

"Point taken," John conceded as he held up his hands in surrender. "Have you eaten today?" Sherlock made no move to reply. "I'll take that as a resounding 'no'. Sit tight. I'll make some stir fry."

John wandered into the kitchen, pulling out some safe-looking beef and the bag of mixed vegetables he brought last Sunday. "Sherlock," he called, opening and closing several drawers, "where's the timer?"

Sherlock snapped his eyes open and stood. "Say that again, John," he said urgently.

"Where's the timer?" He replied slowly as he walked out to Sherlock.

"Oh! John Watson, you are fantastic!" He exclaimed, squeezing John's arm as he bounded past him and out the door.

John just rolled his eyes and set to packing the food back up. There was, apparently, no point in cooking dinner tonight.

* * *

When John woke up the next morning, he was only mildly surprised to find Sherlock still missing. By the way he ran out last night, it was obvious the man was close to a breakthrough in the case. Since it looked like John wouldn't be needed in this one at all, he headed, somewhat disappointed, to his real job at the clinic.

After exchanging the typical pleasantries with Sarah and diagnosing four cases of strep throat, two stomach flus, and a rather bad case of pneumonia, the doctor was ready for a break.

"Sarah," he popped out of his office, "I'm going to lunch."

"Mind if I join you?" His boss asked. "Linda can cover for me."

He smiled fondly. "Of course."

The pair ended up going to a little café down the street. They ate in companionable silence until Sarah finally sighed.

"John," she sat down her utensils, "I know the whole soul mate thing yesterday bothered you. I don't want there to be any bad blood between us. You know, I still consider you one of my dearest friends. I just wish you would open up to me a bit more."

"There isn't any bad blood between us. Honestly. You're a dear friend to me, too. It's just… it's complicated." He cringed even as he said it.

The woman's eyes lit up with mirth as she jumped on his mistake. "John Watson, did you just tell me 'it's complicated'? What's next? 'I just need some space'? 'It's not you, it's me'?" She sniggered.

"Oh, you know what I meant," he mock-glared before dissolving into laughter with her.

Their giggles were cut off by a sudden pinging noise.

Frozen, John whispered "Was that…?"

"It wasn't me this time" Sarah breathed, shaking her head with joyful disbelief.

Repeating the too-familiar motion of pushing back the fabric, John glanced, stunned, at his left wrist. No longer was he greeted by the sight of the taunting dashes. Instead he was greeted by something much more worrying.

"Sarah…?"

"What, John? What is it? How much time do you have?" His boss bounced excitedly, her ponytail swishing comically from side to side.

He blinked up at her. "None."

"What?" She halted.

"I-I don't. None. Just zeros." The man's voice was a horrible mixture of dazed and dejected.

"But it didn't go off. You didn't lock eyes with your soul mate. It just activated. Why…?"

"I don't know," he sat up perfectly straight, looking every bit the army captain he once was, "but I'm going to find out."

"Of course. Don't worry, John, I'll handle things. Just go."

He looked gratefully at her, thankful once more for having such a great friend in Sarah, before marching off to the London TiMER distributer.

He didn't understand. All this time of aching to have his device activated, and this happens?

Yanking open the door, John is greeted by an annoying cheerful voice.

"Hi! I'm Matchmaker Toby" cheered a scruffy-looking boy with a too-wide smile. "How can I help you today?"

Watson bared his wrist to the man. "My TiMER zeroed out, but I haven't met my soul mate yet." His voiced was clipped, but it didn't seem to faze the exuberance of Matchmaker Toby.

"It's not a problem, sir. TiMERs always zero out at midnight, the night before you meet your soul mate. You will meet them any time today! How exciting!"

John clenched his teeth. "No, see, I know that. I mean, my TiMER _activated_ today, just a few minutes ago, and started at zero."

"Oh, dear." The matchmaker looked truly startled. "I've never heard of that happening before. Here, give me your name and birthdate, and I'll check the system." He moved behind the counter, long hair flopping behind him, and shook the mouse of a rather large computer.

"John Hamish Watson, born the 7th of August, 1971." John welled up with anxiety as Matchmaker Toby plucked at the keys.

"How strange. You said you activated today?"

He couldn't stop the slight noise of displeasure that escaped him. "Yes, just a few minutes ago, why?"

"Oh, dear." Matchmaker Toby's dark eyes were apologetic as he looked up a John, which was decidedly _not_ what John was hoping for at the moment. "According to our system, you were meant to meet your soul mate… _years_ ago."

"_Years?"_

"Nearly four, to be precise."

Shit, John thought, that could have been any time after I got back from Afghanistan. He hands fisted at his sides, aching to lash out at something. "I don't… what does that mean?"

"Well," the matchmaker drawled, clearly unhappy with giving this kind of news, "it's possible that you've befriended your soul mate, or it could be someone that you work with or frequently see. In that case, your TiMER could go off the next time you two make eye contact. Although, it's… possible that the opportunity has… passed."

His knuckles turned white. "What you're telling me, Matchmaker Toby, is that there is no way to know when or even _if_ I will be united with my match?"

"Well…" Toby was cut off by a cry from the back room, followed by several clattering and clanging noises. John, ever the soldier, sprang into action as Toby called out "Louisa" in a fearful manner.

The sight John encountered was both entirely unexpected and completely unsurprising. There, in the back room, Sherlock Holmes was grappling with a woman he presumed to be Matchmaker Louisa. Though, really, grappling might have been an exaggeration. The grappling was clearly over. The small bed and computer equipment lay over turned and largely broken, while the consulting detective held the matchmaker down.

Matchmaker Toby produced a startled squeak and started toward Sherlock. Before he could take three steps, John had reached out his arm to stop him.

"Sherlock, what the hell is going on?"

"Oh, John, you're here. Excellent. Phone Lestrade and tell him I've got the Walker killer."

His blasé tone did nothing for John's already worn nerves. He looked down at the struggling woman beneath his friend then over at the confused and slightly appalled Matchmaker Toby before shrugging and pulling out his phone.

Lestrade soon arrived and one of the officers escorted Louisa to a car, as John attempted to console Matchmaker Toby.

"Mind explaining, Sherlock?" He heard Lestrade ask, sounding simultaneously irritated and resigned.

"It was her brother."

"Her brother killed Charles Walker?"

Sherlock sighed heavily, as if greatly disappointed Lestrade hadn't figured out the entire case from those four words. "No, he was the reason she killed Walker." When the DI continued to express his confusion, Sherlock finally launched into the full explanation.

"When I realized that Walker had to have been killed in a public setting without knowledge of being administered the allergen, it became clear to me that it had to have been introduced into his blood stream by inconspicuous methods, something he wouldn't even think about. Charles didn't have an appointment with his doctor, so where else would someone be able to subtly introduce something to his blood? It hit me when I realized that the redness around Walker's wrist wasn't just from the allergic reaction, but also from his TiMER, newly installed.

"Walker and Matchmaker Louisa go to university together; they're both chemistry majors. Walker admired her from afar and eventually convinced himself that Louisa was his soul mate, but she wouldn't give him the proverbial time of day. So, he began dating her seventeen year old brother."

"Seriously?" Lestrade shivered. "What a creep."

"Indeed," Sherlock raised his brow. "Broke his heart when he caught Charles forcing himself on Louisa. Instead of giving in, though, Louisa pretended to be interested in Walker. She told him to get a TiMER so they'd know for sure. She was originally planning on simply getting him to back off by showing him that they weren't soul mates. Once he submitted his personality module, Louisa found out he had a severe allergy to salicylic acid, and a revenge plot came to her mind.

"From there, it was the easiest thing in the world to introduce the salicylic acid into the prongs of the device and take his EpiPen from his bag. She had intended for her homemade, lower concentration allergen to have a milder effect. She didn't realize it would still kill him, just at a slower rate. When she got off work and went to confront him, she found him lying dead in his apartment. Clever girl she is, she wiped down the EpiPen, put some of his prints on it, got an empty jar of aspirin, and set it in his hand to make it look like he had killed himself. His unrequited love for Louisa would have made an excellent motive for his suicide, too." Sherlock tutted with false disappointment.

"And you got all of this… how?"

The real disappointment was back. "I set up an appointment with the matchmakers last night. I went in, deduced that Matchmaker Louisa was the assailant, and had her assist me in filling out the personality modules and installing my TiMER. That was more than enough time to deduce all of the necessary information. After I saw for myself how the installation worked, my theory was confirmed, and I confronted her about the murder. She resisted, I held her down, John arrived, and he called you. You know the rest."

"Right. That's going to be fun to write up. Ta," Lestrade grumbled as he walked back to his squad car.

Glancing over, John realized Matchmaker Toby must have been lead away by an officer at some point during Sherlock's explanation. John shrugged and walked up behind Sherlock.

"That was brilliant."

"Yes, thank you, John." Sherlock spoke as he began to turn around. "I-"

Their eyes met, and, in chorus, two TiMERs pinged. From all over the crime scene, heads snapped toward the two men.

Hurriedly, and mostly out of habit, John pushed the edge of his left sleeve away from his wrist and glanced at the device.

Yes. Yes, of course it was.

"No way," came the nasal voice. "The Freak and his pet?"

Sherlock rolled his eyes. "Yes, obviously, Anderson."

"So what? You knew all along?" He snorted in disbelief.

"Of course I did."

The sentence ripped John out of his daze. "I- we're… you're my… You _knew_?"

The consulting detective's head whipped toward John, momentary shock dancing across his features and seeming so entirely out of place there. Then, deliberately, Sherlock closed the space between them.

For a while, they simply stared at each other: John with confusion and Sherlock with his usual searching gaze. Just as he was starting to become uneasy, Sherlock grabbed the back of John's neck and pulled him into a searing kiss.

It was over too soon, both of them slightly breathless and leaning desperately into the other. Sherlock rested his forehead gently on John's and softly, amazedly, uttered "You _didn't?_"

**A/N:** I hope you liked it! Please review if you feel so inclined. I would greatly appreciate it. Just a couple of quick things:

1. Obviously, I own neither Sherlock nor TiMER.  
2. The title comes from my favorite poem: A Dialogue between the Soul and Body by Andrew Marvell. Go read it. It's Marvell-ous. Get it? *snort*  
3. I honestly couldn't decide whether to put in Mystrade or Lestrolly or Lestrade/OC, so I left it open for whichever the reader decides.  
4. I totally apologize for the case. That was a complete accident. I meant for it to be a background thing, but then... this happened.  
5. This current version is unedited/unbetaed/unbritpicked. Please, don't comment about grammar mistakes or whatever. Honestly, I haven't even read through it once, so it's probably littered with errors, but I will edit it as soon as I can.

Thanks for reading!

-Her Highness


End file.
